Peds Flashcards
What is Pierre Robin sequence associated with?
Micrognathia, glossoptosis, airway obstruction
- must used supraglottic airway on induction
How do you induce a child with Pierre Robin?
With sevoflurane to maintain spontaneous ventilation
What are the conditions associated with the Pierre Robin sequence
Treacher-Collins
FAS
Velocardiofacial
Stickler
What does velocardiofacial look like?
Long face Dark circles under eyes Prominent nose Flattened cheeks Cardiac and palatal anomalies
What is congenital emphysema?
Hyperinflation of one area of the lungs with ball-valve effect
How should a patient with congenital emphysema be induced and why?
With sevoflurane and maintain spontaneous ventilation.
NO nitrous do to increase of bleb and subsequent PTX
NO positive pressure as in controlled ventilation
What are the primary mediators of nonshivering thermogenesis in infacts and neonates?
Norepinephrine
Thyroxin
glucocorticoids
How does nonshivering themogenesis work?
The cold stimulates norepinephrine release which stimulates B receptors in brown fat which uncouples oxidative phosphorylation to make heat instead of ATP through lipase –> release of fatty acids
What inhibits nonshivering thermogenesis?
Inhalational anesthetics
Beta blockers
How does GFR differ in neonates?
It is lower
When does GFR increase in neonates?
At 3-5 weeks when the nephron ages
What is different about the neonate nephron?
The distal tubule cannot absorb sodium because they are resistant to aldosterone.
The collecting tubule is resistant to ADH - cannot hold onto water or sodium!
What is the total body water of a child compared to an adult?
Larger TBW so more sensitive to dehydration
What is the body surface area to body weight ratio of a pediatric patient compared to an adult?
Much higher so more evaporative losses
How do the neonate heart differ from the adult heart?
It is relatively noncompliant with decreased intracellular calcium stores and therefore decreased contractility, so SV is fixed. CO depends solely on HR.
Why else is dehydration dangerous in a child?
Because they cannot compensate as well with heart rate due to PNS predominance and immature baroreceptor reflexes
What is the equation for maintenance fluid?
4 ml/kg/hr for the first 10 kilograms
2 ml/kg/hr for the second 10 kg
1 ml/kg/hr for anything over 20 kg
***If child is over 20 kg just add 40 to the weight
What is the equation for NPO deficit?
Number of hours NPO X maintenance fluid
How do you replace the child’s fluid deficit?
Replace the first half in the first hour of surgery, then one quarter in the second hour, then the last quarter in the third hour
When should blood be the replacement fluid?
When EBL = 20% of blood volume lost because the amount of crystalloid it takes to keep up goes up exponentially
What are patients with Duchenne’s muscular dystrophy at risk for under anesthesia?
- Cardiac dysrhythmias due to imbalance of PNS/SNS and the fibrosis of the conduction system associated with this dz.
- Hyperkalemia and rhabdo due to inhalational anesthetics which disrupt cells and cause an increase in intracellular calcium
What are patients with myotonic dystrophy in danger of?
Severe myotonias that can be caused by anesthetic drugs such as: succinylcholine, acetylcholinesterase inhibitors (neostigmine), potassium containing solutions
What is myotonic dystrophy?
Autosomal dominant disease causing muscle weakness and contractures
What is the first sign of intrathecal injection on a child under 5 years of age?
Apnea
Where does the dural sac end in newborn?
S2-3
Where is the site of injection of caudal anesthesia?
S4-5
What is the chance of an infant having a PTX after meconium aspiration?
10%
What are the clinical signs of neonatal PTX?
Hyperexpansion
Poor excursion
Muffled heart sounds
What is the treatment for neonatal PTX?
22G at 2nd intercostal space, midclavicular line for emergent decompression
What is the appropriate bolus dose of IVF for a hypovolemic pediatric patient?
20 ml/kg of isotonic solution
What can you give the hypovolemic child who is not responsive to a crystalloid bolus?
10 ml/kg salt-poor albumin
What is the best indicator that a patient is optimized after pyloric stenosis for surgery?
Normal chloride because they have hypokalemia hypochloremic metabolic alkalosis due to vomiting HCL
When does surfactant production occur?
By type II pneumocytes after 32 weeks gestation
What are the clinical manifestations of RDS?
Grunting
Nasal flaring
Chest retractions
What is the pathophysiology of RDS?
Decreased surfactant which causes decreased compliance of the lungs, instability at the end of expiration, and low lung volumes as well as increased inflammation and pulmonary edema.
It creates an intrapulmonary shunt and V/Q mismatch leading to hypoxia
What is the treatment for RDS?
Exogenous surfactant
What indicates mature fetal lungs?
A lecithin : sphingomyelin ratio > 2.0 or 3.5 in diabetics
When is lecithin made in the gestational period?
between 24-26 weeks
When are lecithin and sphingomyelin about equal?
32-33 weeks
When does lecithin increase in gestation?
35 weeks
How does hepatic metabolism compare to adults in neonates?y
It is much slower so you have increased duration of action of NMBs that are hepatically meatbolized (vec, roc)
When is there complete maturation of the NMJ?
2 months - diaphragm is paralyzed at the same time as other muscles
What are the risk factors for postop OSA after adenotonsillectomy?
Age < 3 years history of prematurity URI in the past 4 weeks Obesity High Mallampati score Nasal abnormalities Obstruction with inhalational induction HTN, cor pulmonale Difficulty breathing in sleep Disorderd breathing in PACU Craniofacial and neuromuscular disorders